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Spin Current in Spin-Orbit Coupling Systems

Jiangping Hu·Bogdan A. Bernevig·Congjun Wu
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Abstract

We present a simple and pedagogical derivation of the spin current as the linear response to an external electric field for both Rashba and Luttinger spin-orbital coupling Hamiltonians. Except for the adiabatic approximation, our derivation is exact to the linear order of the electric field for both models. The spin current is a direct result of the difference in occupation levels between different bands. Moreover, we show a general topological spin current can be defined for a broad class of spin-orbit coupling systems.

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Jiangping Hu, Bogdan A. Bernevig, Congjun Wu. 2003-10-07. Spin Current in Spin-Orbit Coupling Systems. https://doi.org/10.1142/s0217979203023537

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